Try to support a family on $7/hr. That works out to $14,000/yr if you work the full 40hrs/week. Let's say that your take-home works out to $11,000/yr
Now for a little bit of real-world math:
Small Grungy Apartment: $6000/yr
Public Transit Pass: $1100/yr
That leaves you with a mere $3,900 for food, clothing, utilities etc...
As a father of two girls (4 1/2 months and 2 1/2 years) I can tell you that $325/month won't go very far.